1. Field of the Invention
The present general inventive concept relates to a fusing roller and a fusing device of an electrophotographic image forming apparatus, and more particularly, to a fusing roller which is heated by a wound coil that is connected at an end portion to an external power source, and a fusing device using the fusing roller.
2. Description of the Related Art
Conventional image forming apparatuses, such as laser beam printers, LED printers, digital copy machines, and facsimiles, transfer an image onto a piece of paper according to a digital signal input from a computer or a scanner.
Electrophotographic image forming apparatuses form an electrostatic latent image corresponding to a desired image on the outer circumferential surface of a photoconductor by irradiating light on a predetermined pattern according to a digital signal corresponding to the desired image to be printed, develop the electrostatic latent image using a powder type toner, transfer the electrostatic latent image onto a piece of paper directly or via a transfer medium, and perform a fusing process on the electrostatic latent image.
Thus, the electrophotographic image forming apparatus includes a fusing device which fuses a toner image transferred onto the piece of paper by applying heat and pressure thereto. The fusing device includes a pair of rollers which face each other and rotate. The pair of rollers includes a heat roller which heats the piece of paper using a heat source, such as a halogen lamp or a resistance heating coil, and a pressure roller which faces the heat roller and contacts the heat roller.
If the heat roller is heated using a coil connected to an external power source, a predetermined connection structure, in which an end portion of the coil is connected to the external power source when the heat roller rotates, is provided at an end portion of the heat roller. Such a connection structure normally includes an end cap which rotatably supports the heat roller with respect to a main frame of the image forming apparatus and a connection electrode which is placed in the end cap and connected to the external power source. However, if physical contact between the end portion of the coil and the connection electrode is not ensured by a sufficient bonding force, a short or an arc may occur between the end portion of the coil and the connection electrode.